I follow a similar exchange - on initial contact, "Houston Approach, Tecnam 837 Tango Alpha is with you at 7500" or some such. When they ask for type of aircraft, I usually respond "7 Tango Alpha is a light sport, ICAO identifier Alpha-Sierra-Tango-Oscar." That usually does the trick for ATC and VFR FF, although I occasionally get referred to as an "Aerostar" down the line ... But I don't lead with "light sport" for my SLSA.
Cheers
Part 23 rewrite and LSA's
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